Add backend shape budgets

Author: a19q3

src/codegen/mod.rs

@@ -2266,8 +2266,7 @@ impl CodeGenerator {
                 self.emit("sub t2, t0, t1");
                 let ok_label = self.fresh_label("mutate_preserved_byte_ok");
                 self.emit(format!("beqz t2, {}", ok_label));
-                self.emit("li a0, 13");
-                self.emit_epilogue();
+                self.emit_fail(13);
                 self.emit_label(&ok_label);
             }
         }
@@ -2436,8 +2435,7 @@ impl CodeGenerator {
             self.emit("sub t2, t0, t1");
             let ok_label = self.fresh_label("mutate_transition_ok");
             self.emit(format!("beqz t2, {}", ok_label));
-            self.emit("li a0, 14");
-            self.emit_epilogue();
+            self.emit_fail(14);
             self.emit_label(&ok_label);
         }
     }
@@ -2478,8 +2476,7 @@ impl CodeGenerator {
                 &transition.operand,
                 &format!("{} set.{}", pattern.ty, transition.field),
             ) {
-                self.emit("li a0, 14");
-                self.emit_epilogue();
+                self.emit_fail(14);
             }
         }
     }
@@ -2594,8 +2591,7 @@ impl CodeGenerator {
             self.emit("sub t1, t3, t6"); // diff_hi = actual_hi - expected_hi
             self.emit("or t2, t2, t1"); // combined diff = diff_lo | diff_hi
             self.emit(format!("beqz t2, {}", ok_label));
-            self.emit("li a0, 14");
-            self.emit_epilogue();
+            self.emit_fail(14);
             self.emit_label(&ok_label);
         }
     }
@@ -2619,8 +2615,7 @@ impl CodeGenerator {
         self.emit("sub t2, t0, t1");
         let ok_label = self.fresh_label("output_field_ok");
         self.emit(format!("beqz t2, {}", ok_label));
-        self.emit("li a0, 3");
-        self.emit_epilogue();
+        self.emit_fail(3);
         self.emit_label(&ok_label);
     }
 
@@ -2668,8 +2663,7 @@ impl CodeGenerator {
                     self.emit("sub t2, t0, t1");
                     let ok_label = self.fresh_label("output_byte_ok");
                     self.emit(format!("beqz t2, {}", ok_label));
-                    self.emit("li a0, 3");
-                    self.emit_epilogue();
+                    self.emit_fail(3);
                     self.emit_label(&ok_label);
                 }
             }
@@ -2685,8 +2679,7 @@ impl CodeGenerator {
                     self.emit("sub t2, t0, t1");
                     let ok_label = self.fresh_label("output_byte_ok");
                     self.emit(format!("beqz t2, {}", ok_label));
-                    self.emit("li a0, 3");
-                    self.emit_epilogue();
+                    self.emit_fail(3);
                     self.emit_label(&ok_label);
                 }
             }
@@ -2703,8 +2696,7 @@ impl CodeGenerator {
                     self.emit("sub t2, t0, t1");
                     let ok_label = self.fresh_label("output_byte_ok");
                     self.emit(format!("beqz t2, {}", ok_label));
-                    self.emit("li a0, 3");
-                    self.emit_epilogue();
+                    self.emit_fail(3);
                     self.emit_label(&ok_label);
                 }
             }
@@ -2722,8 +2714,7 @@ impl CodeGenerator {
                     self.emit("sub t2, t0, t1");
                     let ok_label = self.fresh_label("output_byte_ok");
                     self.emit(format!("beqz t2, {}", ok_label));
-                    self.emit("li a0, 3");
-                    self.emit_epilogue();
+                    self.emit_fail(3);
                     self.emit_label(&ok_label);
                 }
             }
@@ -2741,8 +2732,7 @@ impl CodeGenerator {
                     self.emit("sub t2, t0, t1");
                     let ok_label = self.fresh_label("output_byte_ok");
                     self.emit(format!("beqz t2, {}", ok_label));
-                    self.emit("li a0, 3");
-                    self.emit_epilogue();
+                    self.emit_fail(3);
                     self.emit_label(&ok_label);
                 }
             }

tests/examples.rs

@@ -4,10 +4,27 @@ use cellscript::{compile_file, ArtifactFormat, CompileOptions, PoolPrimitiveMeta
 const BUNDLED_EXAMPLES: [&str; 7] =
     ["amm_pool.cell", "launch.cell", "multisig.cell", "nft.cell", "timelock.cell", "token.cell", "vesting.cell"];
 
+const BUNDLED_EXAMPLE_ELF_SIZE_BUDGETS: [(&str, usize); 7] = [
+    ("amm_pool.cell", 56 * 1024),
+    ("launch.cell", 48 * 1024),
+    ("multisig.cell", 40 * 1024),
+    ("nft.cell", 64 * 1024),
+    ("timelock.cell", 40 * 1024),
+    ("token.cell", 24 * 1024),
+    ("vesting.cell", 36 * 1024),
+];
+
 fn example_path(name: &str) -> Utf8PathBuf {
     Utf8PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("examples").join(name)
 }
 
+fn bundled_example_elf_size_budget(name: &str) -> usize {
+    BUNDLED_EXAMPLE_ELF_SIZE_BUDGETS
+        .iter()
+        .find_map(|(example, budget)| (*example == name).then_some(*budget))
+        .expect("missing bundled example ELF size budget")
+}
+
 #[allow(dead_code)]
 struct SchedulerAccessWitness {
     operation: u8,
@@ -293,6 +310,13 @@ fn bundled_examples_compile_to_elf() {
         .unwrap_or_else(|e| panic!("{} should compile to ELF: {}", example, e.message));
 
         assert!(!result.artifact_bytes.is_empty(), "ELF artifact for {} should be non-empty", example);
+        assert!(
+            result.artifact_bytes.len() <= bundled_example_elf_size_budget(example),
+            "ELF artifact for {} grew past its backend shape budget: {} > {} bytes",
+            example,
+            result.artifact_bytes.len(),
+            bundled_example_elf_size_budget(example)
+        );
     }
 }